U.S. patent number 11,193,084 [Application Number 16/193,440] was granted by the patent office on 2021-12-07 for low viscosity lubricating oil compositions.
This patent grant is currently assigned to CHEVRON JAPAN LTD.. The grantee listed for this patent is Chevron Japan Ltd.. Invention is credited to Taiki Hattori, Koichi Kubo, Chihiro Sone, Yoshitaka Takeuchi.
United States Patent |
11,193,084 |
Kubo , et al. |
December 7, 2021 |
Low viscosity lubricating oil compositions
Abstract
Provided is a lubricating oil composition having a HTHS
viscosity at 150.degree. C. in a range of about 1.7 to about 3.2
mPa s and a low temperature cold cranking viscosity of less than
7,000 mPa s at -20.degree. C., comprising: (a) a major amount of an
oil of lubricating viscosity having a kinematic viscosity at
100.degree. C. of from 3.5 mm.sup.2/s to 20 mm.sup.2/s and a
viscosity index of greater than 120 with a sulfur content of less
than 0.03 wt. %, are classified into the API group III, IV, or V
base stock category, and have an aromatics content (C.sub.A) of
less than 5%; (b) an organomolybdenum compound; (c) a dispersed
hydrated alkali metal borate compound; (e) one or more dispersants;
(f) one or more calcium-based metal detergents; and (g) optionally,
one or more magnesium-based metal detergents. Also provided is a
method for improving wear, high temperature detergency, and thermal
stability in an engine comprising operating said engine with said
lubricating oil composition.
Inventors: |
Kubo; Koichi (Yokohama,
JP), Takeuchi; Yoshitaka (Yoshida-Cho, JP),
Hattori; Taiki (Kakegawa, JP), Sone; Chihiro
(Makinohara, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
Chevron Japan Ltd. |
San Ramon |
CA |
US |
|
|
Assignee: |
CHEVRON JAPAN LTD. (Tokyo,
JP)
|
Family
ID: |
68654828 |
Appl.
No.: |
16/193,440 |
Filed: |
November 16, 2018 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20200157460 A1 |
May 21, 2020 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10M
129/50 (20130101); C10M 133/12 (20130101); C10M
137/10 (20130101); C10M 135/10 (20130101); C10M
169/045 (20130101); C10M 141/10 (20130101); C10M
129/54 (20130101); C10M 133/44 (20130101); C10M
169/04 (20130101); C10M 125/26 (20130101); C10N
2030/04 (20130101); C10M 2223/045 (20130101); C10M
2219/046 (20130101); C10M 2215/28 (20130101); C10M
2219/044 (20130101); C10M 2215/064 (20130101); C10M
2227/066 (20130101); C10N 2030/44 (20200501); C10N
2030/45 (20200501); C10M 2207/144 (20130101); C10N
2030/10 (20130101); C10M 2207/262 (20130101); C10N
2040/253 (20200501); C10N 2030/02 (20130101); C10N
2040/25 (20130101); C10M 2205/0285 (20130101); C10N
2030/40 (20200501); C10M 2203/1006 (20130101); C10N
2030/08 (20130101); C10M 2205/022 (20130101); C10M
2207/028 (20130101); C10M 2207/141 (20130101); C10N
2030/42 (20200501); C10N 2030/43 (20200501); C10M
2203/1025 (20130101); C10M 2209/084 (20130101); C10N
2030/06 (20130101); C10M 2201/087 (20130101); C10M
2215/26 (20130101); C10M 2215/30 (20130101); C10M
2205/022 (20130101); C10M 2205/024 (20130101); C10M
2215/28 (20130101); C10N 2010/12 (20130101); C10M
2203/1025 (20130101); C10N 2020/02 (20130101); C10M
2201/087 (20130101); C10N 2010/02 (20130101); C10M
2223/045 (20130101); C10N 2010/04 (20130101); C10M
2207/028 (20130101); C10N 2010/04 (20130101); C10M
2207/262 (20130101); C10N 2010/04 (20130101); C10M
2219/046 (20130101); C10N 2010/04 (20130101); C10M
2215/28 (20130101); C10N 2060/06 (20130101); C10M
2215/28 (20130101); C10N 2060/14 (20130101) |
Current International
Class: |
C10M
169/04 (20060101); C10M 135/18 (20060101); C10M
161/00 (20060101); C10M 125/26 (20060101); C10M
129/50 (20060101); C10M 133/12 (20060101); C10M
133/44 (20060101); C10M 135/10 (20060101); C10M
137/10 (20060101); C10M 141/10 (20060101); C10M
141/12 (20060101); C10M 145/14 (20060101); C10M
129/54 (20060101); C10M 139/00 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1167497 |
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Jan 2002 |
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EP |
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1918357 |
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May 2008 |
|
EP |
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2428551 |
|
Mar 2012 |
|
EP |
|
Other References
International Search Report, dated Feb. 7, 2020, during the
prosecution of International Application No. PCT/IB2019/059726.
cited by applicant .
Written Opinion of the International Searching Authority, dated
Feb. 7, 2020, during the prosecution of International Application
No. PCT/IB2019/059726. cited by applicant.
|
Primary Examiner: McAvoy; Ellen M
Assistant Examiner: Graham; Chantel L
Claims
What is claimed is:
1. A lubricating oil composition having a HTHS viscosity at
150.degree. C. in a range of about 1.7 to about 3.2 mPa s and a low
temperature cold cranking viscosity of less than 7,000 mPa s at
-20.degree. C., comprising: (a) a major amount of an oil of
lubricating viscosity having a kinematic viscosity at 100.degree.
C. of from 3.5 mm.sup.2/s to 20 mm.sup.2/s and a viscosity index of
greater than 120 with a sulfur content of less than 0.03 wt. %, are
classified into the API group III, IV, or V base stock category,
and have an aromatics content (C.sub.A) of less than 5%; (b) an
organomolybdenum compound providing greater than 0.0050 wt. % of
molybdenum to the lubricating oil composition; (c) a dispersed
hydrated alkali metal borate compound providing greater than 0.0050
to about 0.060 wt. % of alkali metal to the lubricating oil
composition; (d) a sulfur phosphorus anti-wear compound providing
the lubricating oil composition with from 0 to about 0.06 wt. % of
phosphorus; (e) one or more dispersants providing the lubricating
oil composition with greater than 0.0050 to about 0.040 wt. % of
nitrogen; and (f) one or more calcium-based metal detergents
selected from salicylate, sulfonate, and phenate; (g) optionally,
one or more magnesium-based metal detergents selected from
salicylate, sulfonate, and phenate; and wherein the lubricating oil
composition has a calcium content of from about 0.14 to about 0.30
wt. %, when present a magnesium content of from about 0.0005 to
about 0.060 wt. %, a total nitrogen amount of from 0.0050 to about
0.090 wt. %, sulfur content of less than 0.13 wt. % and a sulfated
ash level of from about 0.6 to about 1.1 wt. %.
2. The lubricating oil composition of claim 1, wherein the
organomolybdenum compound provides from about 0.0050 to about 0.050
wt. % of molybdenum to the lubricating oil composition.
3. The lubricating oil composition of claim 1, wherein the
dispersed hydrated alkali metal borate compound provides from about
0.0050 to about 0.10 wt. % of boron to the lubricating oil
composition.
4. The lubricating oil composition of claim 1, wherein phosphorus
is present from 0 to about 0.04 wt. % based on the total weight of
lubricating oil composition.
5. The lubricating oil composition of claim 1, wherein phosphorus
is present from 0 to about 0.03 wt. % based on the total weight of
lubricating oil composition.
6. The lubricating oil composition of claim 1, wherein the
lubricating oil composition is free of phosphorus.
7. The lubricating oil composition of claim 1, wherein sulfur is
present from about 0.01 to about 0.4 wt. % based on the total
weight of the lubricating oil composition.
8. The lubricating oil composition of claim 1, wherein sulfated ash
is present from about 1.1 to about 0.6 wt. % based on the total
weight of the lubricating oil composition.
9. The lubricating oil composition of claim 1, wherein the
lubricating oil composition is a 0W-8, 0W-12, 0W-16, or 0W-20 SAE
viscosity grade.
10. The lubricating oil composition of claim 1, wherein the
lubricating oil composition has a HTHS viscosity at 150.degree. C.
in a range of about 2.0 to about 3.6 mPa s.
11. The lubricating oil composition of claim 1, wherein the
lubricating oil composition has a kinematic viscosity at
100.degree. C. of from 3.5 mm.sup.2/s to 12 mm.sup.2/s.
12. The lubricating oil composition of claim 1, wherein the
lubricating oil is selected from one or more of API Group III, IV,
and V.
13. A method for improving wear, high temperature detergency, and
thermal stability in an engine comprising operating said engine
with a lubricating oil composition having a HTHS viscosity at
150.degree. C. in a range of about 1.7 to about 3.2 mPa s and a low
temperature cold cranking viscosity of less than 7,000 mPa s at
-20.degree. C., comprising: (a) a major amount of an oil of
lubricating viscosity having a kinematic viscosity at 100.degree.
C. of from 3.5 mm.sup.2/s to 20 mm.sup.2/s and a viscosity index of
greater than 120 with a sulfur content of less than 0.03 wt. %, are
classified into the API group III, IV, or V base stock category,
and have an aromatics content (C.sub.A) of less than 5%; (b) an
organomolybdenum compound providing greater than 0.0050 wt. % of
molybdenum to the lubricating oil composition; (c) a dispersed
hydrated alkali metal borate compound providing greater than 0.0050
to about 0.060 wt. % of alkali metal to the lubricating oil
composition; (d) a sulfur phosphorus anti-wear compound providing
the lubricating oil composition with from 0 to about 0.06 wt. % of
phosphorus; (e) one or more dispersants providing the lubricating
oil composition with greater than 0.005 to about 0.040 wt. % of
nitrogen; and (f) one or more calcium-based metal detergents
selected from salicylate, sulfonate, and phenate; (g) optionally,
one or more magnesium-based metal detergents selected from
salicylate, sulfonate, and phenate; and wherein the lubricating oil
composition has a calcium content of from about 0.14 to about 0.30
wt. %, when present a magnesium content of from about 0.0005 to
about 0.060 wt. %, a total nitrogen amount of from 0.0050 to about
0.090 wt. %, sulfur content of less than 0.13 wt. % and a sulfated
ash level of from about 0.6 to about 1.1 wt. %.
14. The method of claim 13, wherein the organomolybdenum compound
provides from about 0.0050 to about 0.050% wt of molybdenum to the
lubricating oil composition.
15. The method of claim 13, wherein the dispersed hydrated alkali
metal borate compound provides from about 0.0050 to about 0.10 wt.
% of boron to the lubricating oil composition.
16. The method of claim 13, wherein phosphorus is present from 0 to
about 0.04 wt. % based on the total weight of lubricating oil
composition.
17. The method of claim 13, wherein phosphorus is present from 0 to
about 0.03 wt. % based on the total weight of lubricating oil
composition.
18. The method of claim 13, wherein the lubricating oil composition
is free of phosphorus.
19. The method of claim 13, wherein sulfur is present from about
0.01 to about 0.4 wt. % based on the total weight of the
lubricating oil composition.
20. The method of claim 13, wherein sulfated ash is present from
about 1.1 to about 0.6 wt. % based on the total weight of the
lubricating oil composition.
21. The method of claim 13, wherein the lubricating oil composition
is a 0W-8, 0W-12, 0W-16, or 0W-20 SAE viscosity grade.
22. The method of claim 13, wherein the lubricating oil composition
has a HTHS viscosity at 150.degree. C. in a range of about 2.0 to
about 3.6 mPa s.
23. The method of claim 13, wherein the lubricating oil composition
has a kinematic viscosity at 100.degree. C. of from 3.5 mm.sup.2/s
to 12 mm.sup.2/s.
24. The method of claim 13, wherein the lubricating oil is selected
from one or more of API Group III, IV, and V.
Description
BACKGROUND OF THE DISCLOSURE
Engine oil is usually blended with various additives in order to
satisfy various performance requirements. One well known way to
increase fuel economy is to decrease the viscosity of the
lubricating oil. Most internal combustion engine oils, which
demonstrate excellent fuel economy performance, are usually
formulated to be low viscosity oils with a viscosity improver to
reduce fluid friction from viscosity resistance under low
temperature. In order to improve fuel efficiency, many original
equipment manufacturers (OEM's) are looking at shifting to
downsized turbo diesel (DE) and gasoline direct injection (GDI)
engines for the improvement of fuel efficiency. The drawback to
this is poor wear and engine durability, especially due to low
viscosity with severe operating temperature and soot in oil
conditions.
Further, to meet emission regulations, there is a need to reduce
antiwear additive systems containing phosphorus, sulfur, and/or
metals such as Zinc Dialkyldithiophosphate (ZnDTP). ZnDTP is a
versatile anti-wear/anti-oxidant component that provides good wear
and favorable oxidation protection under severe conditions.
However, ZnDTPs comprise the elements zinc, sulfur and phosphorus
which all have negative impact on exhaust after-treatment
devices.
The inventors have discovered lubricating oil compositions which
have good fuel efficiency and anti-wear properties with low SAE
viscosity grade oils, even when the level of ZnDTP is reduced, or
free of zinc and phosphorus.
SUMMARY OF THE DISCLOSURE
The present disclosure generally relates to a lubricating oil
composition a HTHS viscosity at 150.degree. C. in a range of about
1.7 to about 3.2 mPa s and a low temperature cold cranking
viscosity of less than 7,000 mPa s at -20.degree. C.,
comprising:
(a) a major amount of an oil of lubricating viscosity having a
kinematic viscosity at 100.degree. C. of from 3.5 mm.sup.2/s to 20
mm.sup.2/s and a viscosity index of greater than 120 with a sulfur
content of less than 0.03 wt. %, are classified into the API group
III, IV, or V base stock category, and have an aromatics content
(C.sub.A) of less than 5%;
(b) an organomolybdenum compound providing greater than 0.0050 wt.
% of molybdenum to the lubricating oil composition;
(c) a dispersed hydrated alkali metal borate compound providing
greater than 0.0050 to about 0.060 wt. % of alkali metal to the
lubricating oil composition;
(d) a sulfur phosphorus anti-wear compound providing the
lubricating oil composition with from 0 to about 0.06 wt. % of
phosphorus;
(e) one or more dispersants providing the lubricating oil
composition with greater than 0.0050 to about 0.040 wt. % of
nitrogen; and
(f) one or more calcium-based metal detergents selected from
salicylate, sulfonate, and phenate;
(g) optionally, one or more magnesium-based metal detergents
selected from salicylate, sulfonate, and phenate; and
wherein the lubricating oil composition has a calcium content of
from about 0.14 to about 0.30 wt. %, when present a magnesium
content of from about 0.0005 to about 0.060 wt. %, a total nitrogen
amount of from 0.0050 to about 0.090 wt. %, sulfur content of less
than 0.13 wt. % and a sulfated ash level of from about 0.6 to about
1.1 wt. %.
Also provided are methods for improving wear, high temperature
detergency, and thermal stability in an engine comprising operating
said engine with a lubricating oil composition having a HTHS
viscosity at 150.degree. C. in a range of about 1.7 to about 3.2
mPa s and a low temperature cold cranking viscosity of less than
7,000 mPa s at -20.degree. C., comprising:
(a) a major amount of an oil of lubricating viscosity having a
kinematic viscosity at 100.degree. C. of from 3.5 mm.sup.2/s to 20
mm.sup.2/s and a viscosity index of greater than 120 with a sulfur
content of less than 0.03 wt. %, are classified into the API group
III, IV, or V base stock category, and have an aromatics content
(C.sub.A) of less than 5%;
(b) an organomolybdenum compound providing greater than 0.0050 wt.
% of molybdenum to the lubricating oil composition;
(c) a dispersed hydrated alkali metal borate compound providing
greater than 0.0050 to about 0.060 wt. % of alkali metal to the
lubricating oil composition;
(d) a sulfur phosphorus anti-wear compound providing the
lubricating oil composition with from 0 to about 0.06 wt. % of
phosphorus;
(e) one or more dispersants providing the lubricating oil
composition with greater than 0.0050 to about 0.040 wt. % of
nitrogen; and
(f) one or more calcium-based metal detergents selected from
salicylate, sulfonate, and phenate;
(g) optionally, one or more magnesium-based metal detergents
selected from salicylate, sulfonate, and phenate; and
wherein the lubricating oil composition has a calcium content of
from about 0.14 to about 0.30 wt. %, when present a magnesium
content of from about 0.0005 to about 0.060 wt. %, a total nitrogen
amount of from 0.0050 to about 0.090 wt. %, sulfur content of less
than 0.13 wt. % and a sulfated ash level of from about 0.6 to about
1.1 wt. %.
DETAILED DESCRIPTION OF THE DISCLOSURE
To facilitate the understanding of the subject matter disclosed
herein, a number of terms, abbreviations or other shorthand as used
herein are defined below. Any term, abbreviation or shorthand not
defined is understood to have the ordinary meaning used by a
skilled artisan contemporaneous with the submission of this
application.
Definitions
In this specification, the following words and expressions, if and
when used, have the meanings given below.
A "major amount" means in excess of 50 weight % of a
composition.
A "minor amount" means less than 50 weight % of a composition,
expressed in respect of the stated additive and in respect of the
total mass of all the additives present in the composition,
reckoned as active ingredient of the additive or additives.
"Active ingredients" or "actives" refers to additive material that
is not diluent or solvent.
All percentages reported are weight % on an active ingredient basis
(i.e., without regard to carrier or diluent oil) unless otherwise
stated.
The abbreviation "ppm" means parts per million by weight, based on
the total weight of the lubricating oil composition.
High temperature high shear (HTHS) viscosity at 150.degree. C. was
determined in accordance with ASTM D4683.
Kinematic viscosity at 100.degree. C. (KV.sub.100) was determined
in accordance with ASTM D445.
Metal--The term "metal" refers to alkali metals, alkaline earth
metals, or mixtures thereof.
Throughout the specification and claims the expression oil soluble
or dispersible is used. By oil soluble or dispersible is meant that
an amount needed to provide the desired level of activity or
performance can be incorporated by being dissolved, dispersed or
suspended in an oil of lubricating viscosity. Usually, this means
that at least about 0.001% by weight of the material can be
incorporated in a lubricating oil composition. For a further
discussion of the terms oil soluble and dispersible, particularly
"stably dispersible", see U.S. Pat. No. 4,320,019 which is
expressly incorporated herein by reference for relevant teachings
in this regard.
The term "sulfated ash" as used herein refers to the
non-combustible residue resulting from detergents and metallic
additives in lubricating oil. Sulfated ash may be determined using
ASTM Test D874.
The term "Total Base Number" or "TBN" as used herein refers to the
amount of base equivalent to milligrams of KOH in one gram of
sample. Thus, higher TBN numbers reflect more alkaline products,
and therefore a greater alkalinity. TBN was determined using ASTM D
2896 test.
Boron, calcium, magnesium, molybdenum, phosphorus, sulfur, and zinc
contents were determined in accordance with ASTM D5185.
All ASTM standards referred to herein are the most current versions
as of the filing date of the present application.
While the disclosure is susceptible to various modifications and
alternative forms, specific embodiments thereof are herein
described in detail. It should be understood, however, that the
description herein of specific embodiments is not intended to limit
the disclosure to the particular forms disclosed, but on the
contrary, the intention is to cover all modifications, equivalents,
and alternatives falling within the spirit and scope of the
disclosure as defined by the appended claims.
Note that not all of the activities described in the general
description or the examples are required, that a portion of a
specific activity may not be required, and that one or more further
activities may be performed in addition to those described. Still
further, the order in which activities are listed is not
necessarily the order in which they are performed.
Benefits, other advantages, and solutions to problems have been
described herein with regard to specific embodiments. However, the
benefits, advantages, solutions to problems, and any feature(s)
that may cause any benefit, advantage, or solution to occur or
become more pronounced are not to be construed as a critical,
required, or essential feature of any or all the claims.
The specification and illustrations of the embodiments described
herein are intended to provide a general understanding of the
structure of the various embodiments.
As used herein, the terms "comprises," "comprising," "includes,"
"including," "has," "having," or any other variation thereof, are
intended to cover a non-exclusive inclusion. For example, a
process, method, article, or apparatus that comprises a list of
features is not necessarily limited only to those features but may
include other features not expressly listed or other features that
are inherent to such process, method, article, or apparatus.
Further, unless expressly stated to the contrary, "or" refers to an
inclusive-or and not to an exclusive-or. For example, a condition A
or B is satisfied by any one of the following: A is true (or
present) and B is false (or not present), A is false (or not
present) and B is true (or present), and both A and B are true (or
present).
The use of "a" or "an" is employed to describe elements and
components described herein. This is done merely for convenience
and to give a general sense of the scope of the embodiments of the
disclosure. This description should be read to include one or at
least one and the singular also includes the plural, or vice versa,
unless it is clear that it is meant otherwise. The term "averaged,"
when referring to a value, is intended to mean an average, a
geometric mean, or a median value. Group numbers corresponding to
columns within the Periodic Table of the elements use the "New
Notation" convention as seen in the CRC Handbook of Chemistry and
Physics, 81st Edition (2000-2001).
Unless otherwise defined, all technical and scientific terms used
herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this disclosure belongs. The
materials, methods, and examples are illustrative only and not
intended to be limiting. To the extent not described herein, many
details regarding specific materials and processing acts are
conventional and may be found in textbooks and other sources within
the lubricants as well as the oil and gas industries.
The specification and illustrations are not intended to serve as an
exhaustive and comprehensive description of all the elements and
features of formulations, compositions, apparatus and systems that
use the structures or methods described herein. Separate
embodiments may also be provided in combination in a single
embodiment, and conversely, various features that are, for brevity,
described in the context of a single embodiment, may also be
provided separately or in any sub-combination. Further, reference
to values stated in ranges includes each and every value within
that range. Many other embodiments may be apparent to skilled
artisans only after reading this specification. Other embodiments
may be used and derived from the disclosure, such that a structural
substitution, logical substitution, or another change may be made
without departing from the scope of the disclosure. Accordingly,
the disclosure is to be regarded as illustrative rather than
restrictive.
In one aspect, the disclosure provides a lubricating oil
composition having a HTHS viscosity at 150.degree. C. in a range of
about 1.7 to about 3.7 mPa s and a low temperature cold cranking
viscosity of less than 7,000 mPa s at -20.degree. C.,
comprising:
(a) a major amount of an oil of lubricating viscosity having a
kinematic viscosity at 100.degree. C. of from 3.5 mm.sup.2/s to 20
mm.sup.2/s and a viscosity index of greater than 120 and are
classified into the API group III, IV or V base stock category;
(b) an organomolybdenum compound providing greater than 0.0050 wt.
% of molybdenum to the lubricating oil composition;
(c) a dispersed hydrated alkali metal borate compound providing
greater than 0.0050 wt. % of boron to the lubricating oil
composition;
(d) a sulfur phosphorus anti-wear compound providing the
lubricating oil composition with from 0 to about 0.06 wt. % of
phosphorus;
(e) one or more dispersants providing the lubricating oil
composition with greater than 0.008 wt. % of nitrogen; and
(f) one or more calcium-based metal detergents selected from
salicylate, sulfonate, and phenate;
(g) optionally, one or more magnesium-based metal detergents
selected from salicylate, sulfonate, and phenate; and
wherein the lubricating oil composition has a calcium content of
from about 0.12 wt. % to about 0.30 wt. %, when present a magnesium
content of from about 0.0005 wt. % to about 0.060 wt. %, sulfur
content of less than 0.3 wt. % and a sulfated ash level of from
about 0.6 to about 1.1 wt. %.
Oil of Lubricating Viscosity
The oil of lubricating viscosity (sometimes referred to as "base
stock" or "base oil") is the primary liquid constituent of a
lubricant, into which additives and possibly other oils are
blended, for example to produce a final lubricant (or lubricant
composition). A base oil is useful for making concentrates as well
as for making lubricating oil compositions therefrom and may be
selected from natural and synthetic lubricating oils and
combinations thereof.
Natural oils include animal and vegetable oils, liquid petroleum
oils and hydrorefined, solvent-treated mineral lubricating oils of
the paraffinic, naphthenic and mixed paraffinic-naphthenic types.
Oils of lubricating viscosity derived from coal or shale are also
useful base oils.
Synthetic lubricating oils include hydrocarbon oils such as
polymerized and interpolymerized olefins (e.g., polybutylenes,
polypropylenes, propylene-isobutylene copolymers, chlorinated
polybutylenes, poly(l-hexenes), poly(l-octenes), poly(l-decenes);
alkylbenzenes (e.g., dodecylbenzenes, tetradecylbenzenes,
dinonylbenzenes, di(2-ethylhexyl)benzenes, Alkylated Naphthalene;
polyphenols (e.g., biphenyls, terphenyls, alkylated polyphenols);
and alkylated diphenyl ethers and alkylated diphenyl sulfides and
the derivatives, analogues and homologues thereof.
Another suitable class of synthetic lubricating oils comprises the
esters of dicarboxylic acids (e.g., malonic acid, alkyl malonic
acids, alkenyl malonic acids, succinic acid, alkyl succinic acids
and alkenyl succinic acids, maleic acid, fumaric acid, azelaic
acid, suberic acid, sebacic acid, adipic acid, linoleic acid dimer,
phthalic acid) with a variety of alcohols (e.g., butyl alcohol,
hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, ethylene
glycol, diethylene glycol monoether, propylene glycol). Specific
examples of these esters include dibutyl adipate, di(2-ethylhexyl)
sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl
azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate,
dieicosyl sebacate, the 2-ethylhexyl diester of linoleic acid
dimer, and the complex ester formed by reacting one mole of sebacic
acid with two moles of tetraethylene glycol and two moles of
2-ethylhexanoic acid.
Esters useful as synthetic oils also include those made from
C.sub.5 to C.sub.12 monocarboxylic acids and polyols, and polyol
ethers such as neopentyl glycol, trimethylolpropane,
pentaerythritol, dipentaerythritol and tripentaerythritol.
The base oil may be derived from Fischer-Tropsch synthesized
hydrocarbons. Fischer-Tropsch synthesized hydrocarbons are made
from synthesis gas containing H.sub.2 and CO using a
Fischer-Tropsch catalyst. Such hydrocarbons typically require
further processing in order to be useful as the base oil. For
example, the hydrocarbons may be hydroisomerized; hydrocracked and
hydroisomerized; dewaxed; or hydroisomerized and dewaxed; using
processes known to those skilled in the art.
Unrefined, refined and re-refined oils can be used in the present
lubricating oil composition. Unrefined oils are those obtained
directly from a natural or synthetic source without further
purification treatment. For example, a shale oil obtained directly
from retorting operations, a petroleum oil obtained directly from
distillation or ester oil obtained directly from an esterification
process and used without further treatment would be unrefined oil.
Refined oils are similar to the unrefined oils except they have
been further treated in one or more purification steps to improve
one or more properties. Many such purification techniques, such as
distillation, solvent extraction, acid or base extraction,
filtration and percolation are known to those skilled in the
art.
Re-refined oils are obtained by processes similar to those used to
obtain refined oils applied to refined oils which have been already
used in service. Such re-refined oils are also known as reclaimed
or reprocessed oils and often are additionally processed by
techniques for approval of spent additive and oil breakdown
products.
Hence, the base oil which may be used to make the present
lubricating oil composition may be selected from any of the base
oils in Groups I-V as specified in the American Petroleum Institute
(API) Base Oil Interchangeability Guidelines (API Publication
1509). Such base oil groups are summarized in Table 1 below:
TABLE-US-00001 TABLE 1 Base Oil Properties Group.sup.(a)
Saturate.sup.(b), wt. % Sulfur.sup.(c), wt. % Viscosity
Index.sup.(d) Group I <90 and/or >0.03 80 to <120 Group II
.gtoreq.90 .ltoreq.0.03 80 to <120 Group III .gtoreq.90
.ltoreq.0.03 .gtoreq.120 Group IV Polyalphaolefins (PAOs) Group V
All other base stocks not included in Groups I, II, III or IV
.sup.(a)Groups I-III are mineral oil base stocks.
.sup.(b)Determined in accordance with ASTM D2007.
.sup.(c)Determined in accordance with ASTM D2622, ASTM D3120, ASTM
D4294 or ASTM D4927. .sup.(d)Determined in accordance with ASTM
D2270.
In one embodiment, the base oils suitable for use herein are API
Group Group III, Group IV, and Group V oils, and combinations
thereof, due to their exceptional volatility, stability,
viscometric and cleanliness features.
In another embodiment, the base oil has an aromatics content
(C.sub.A) of less than 5%. In other embodiments, the base oil has
an aromatics content (C.sub.A) of less than 4%, less than 3%, less
than 2%, less than 1%. The oil of lubricating viscosity for use in
the lubricating oil compositions of this disclosure, also referred
to as a base oil, is typically present in a major amount, e.g., an
amount of greater than 50 wt. %, preferably greater than about 70
wt. %, more preferably from about 80 to about 99.5 wt. % and most
preferably from about 85 to about 98 wt. %, based on the total
weight of the composition. The expression "base oil" as used herein
shall be understood to mean a base stock or blend of base stocks
which is a lubricant component that is produced by a single
manufacturer to the same specifications (independent of feed source
or manufacturer's location); that meets the same manufacturer's
specification; and that is identified by a unique formula, product
identification number, or both. The base oil for use herein can be
any presently known or later-discovered oil of lubricating
viscosity used in formulating lubricating oil compositions for any
and all such applications, e.g., engine oils, marine cylinder oils,
functional fluids such as hydraulic oils, gear oils, transmission
fluids, etc. Additionally, the base oils for use herein can
optionally contain viscosity index improvers, e.g., polymeric
alkylmethacrylates; olefinic copolymers, e.g., an
ethylene-propylene copolymer or a styrene-butadiene copolymer; and
the like and mixtures thereof. The topology of viscosity modifier
could include, but is not limited to, linear, branched,
hyperbranched, star, or comb topology.
As one skilled in the art would readily appreciate, the viscosity
of the base oil is dependent upon the application. Accordingly, the
viscosity of a base oil for use herein will ordinarily range from
about 2 to about 2000 centistokes (cSt) at 100.degree. Centigrade
(C.). Generally, individually the base oils used as engine oils
will have a kinematic viscosity range at 100.degree. C. of about 2
cSt to about 30 cSt, preferably about 3 cSt to about 16 cSt, and
most preferably about 4 cSt to about 12 cSt and will be selected or
blended depending on the desired end use and the additives in the
finished oil to give the desired grade of engine oil, e.g., a
lubricating oil composition having an SAE Viscosity Grade of 0W,
0W-8, 0W-12, 0W-16, 0W-20, 0W-30, 0W-40, 5W, 5W-16, 5W-20, 5W-30,
5W-40, 10W, 10W-20, 10W-30, 10W-40, 15W, 15W-20, 15W-30, 15W-40 and
the like.
Preferably, the base oil has a viscosity index of greater than 120
(e.g., greater than 125, greater than 130, greater than 135 or
greater than 140). If the viscosity index is less than 120, not
only viscosity-temperature properties, heat and oxidation
stability, and anti-volatilization are reduced, but also the
coefficient of friction tends to be increased, and resistance
against wear tends to be reduced.
Preferably, a sulfur content of the base oil is equal to or less
than 0.03 wt. % (e.g. less than 0.02 wt. %, less than 0.01 wt. % or
less than 0.005 wt. %. If the sulfur content is higher than 0.03
wt. %, not only thermal and oxidation stability are reduced, but
also corrosion to non-ferrous metals, ex. Cu and its alloys at
higher temperature become stronger.
The lubricating oil composition has a viscosity index of at least
135 (e.g., 135 to 400, or 135 to 250), at least 150 (e.g., 150 to
400, 150 to 250), at least 160 (e.g., 160 to 400, or 160 to
250).--If the viscosity index of the lubricating oil composition is
less than 135, it may be difficult to improve fuel efficiency while
maintaining the HTHS viscosity at 150.degree. C. If the viscosity
index of the lubricating oil composition exceeds 400, evaporation
properties may be reduced, and deficits due to insufficient
solubility of the additive and matching properties with a seal
material may be caused.
The lubricating oil composition has a high temperature shear (HTHS)
viscosity at 150.degree. C. of about 1.7 to about 3.2 mPa s, about
2.0 to 3.1 mPa a, about 2.0 to about 3.0, or about 2.0 to about
2.9.
The lubricating oil composition has a kinematic viscosity at
100.degree. C. in a range of 3.5 to 20 mm.sup.2/s (e.g., 3.5 to 20
mm.sup.2/s, 3.8 to 20 mm.sup.2/s, 3.8 to 16.3 mm.sup.2/s, 4 to 12.5
mm.sup.2/s or 4 to 9.3 mm.sup.2/s).
The lubricating oil composition has a low temperature cold cranking
viscosity of less than 7000 mPa s at -20.degree. C. (e.g. less than
7000 mPa s at -25.degree. C., less than 6600 mPa s at -30.degree.
C. or less than 6200 mPa s at -35.degree. C.).
The Molybdenum Containing Compound
The organomolybdenum compound contains at least molybdenum, carbon
and hydrogen atoms, but may also contain sulfur, phosphorus,
nitrogen and/or oxygen atoms. Suitable organomolybdenum compounds
include molybdenum dithiocarbamates, molybdenum dithiophosphates,
and various organic molybdenum complexes such as molybdenum
carboxylates, molybdenum esters, molybdenum amines, molybdenum
amides, which can be obtained by reacting molybdenum oxide or
ammonium molybdates with fats, glycerides or fatty acids, or fatty
acid derivatives (e.g., esters, amines, amides). The term "fatty"
means a carbon chain having 10 to 22 carbon atoms, typically a
straight carbon chain.
Molybdate esters can be prepared by methods disclosed in U.S. Pat.
Nos. 4,889,647 and 6,806,241B2. A commercial example is
MOLYVAN.RTM. 855 additive, which is manufactured by R. T.
Vanderbilt Company, Inc.
Molybdenum dithiocarbamate (MoDTC) is an organomolybdenum compound
represented by the following structure (I):
##STR00001## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are
independently of each other, linear or branched alkyl groups having
from 4 to 18 carbon atoms (e.g., 8 to 13 carbon atoms).
Preparations of these compounds are well known in the literature
and U.S. Pat. Nos. 3,356,702 and 4,098,705 are incorporated herein
for reference. Commercial examples include MOLYVAN.RTM. 807,
MOLYVAN.RTM. 822, and MOLYVAN.RTM. 2000, which are manufactured by
R. T. Vanderbilt Company Inc., SAKURA-LUBE.RTM. 165 and
SAKURA-LUBE.RTM. 515, which are manufactured by ADEKA CORPORATION
and Naugalube.RTM. MolyFM which is manufactured by Chemtura
Corporation.
Trinulcear molybdenum dialkyldithiocarbamates are also known in the
art, as taught by U.S. Pat. Nos. 5,888,945 and 6,010,987, herein
incorporated by reference. Trinuclear molybdenum compounds
preferably those having the formulas Mo.sub.3S.sub.4(dtc).sub.4 and
Mo.sub.3S.sub.7(dtc).sub.4 and mixtures thereof wherein dtc
represents independently selected diorganodithiocarbamate ligands
containing independently selected organo groups and wherein the
ligands have a sufficient number of carbon atoms among all the
organo groups of the compound's ligands are present to render the
compound soluble or dispersible in the lubricating oil.
Molybdenum dithiophosphate (MoDTP) is an organomolybdenum compound
represented by the following structure (II):
##STR00002## wherein R.sup.5, R.sup.6, R.sup.7 and R.sup.8 are
independently of each other, linear or branched alkyl groups having
from 4 to 18 carbon atoms (e.g., 8 to 13 carbon atoms).
Molybdenum carboxylates are described in U.S. No. Pat. RE 38,929,
and U.S. Pat. No. 6,174,842 and thus are incorporated herein by
reference. Molybdenum carboxylates can be derived from any oil
soluble carboxylic acid. Typical carboxylic acids include
naphthenic acid, 2-ethylhexanoic acid, and linolenic acid.
Commercial sources of carboxylates produce from these particular
acids are MOLYBDENUM NAP-ALL, MOLYBDENUM HEX-CEM, and MOLYBDENUM
LIN-ALL respectively. Manufacturer of these products is OMG OM
Group.
Ammonium molybdates are prepared by the acidibase reaction of
acidic molybdenum source such as molybdenum trioxide, molybdic
acid, and ammonium molybdate and ammonium thiomolybdates with
oil-soluble amines and optionally in presence of sulfur sources
such sulfur, inorganic sulfides and polysulfides, and carbons
disulfide to name few. The preferred aminic compounds are polyamine
dispersants that are commonly used engine oil compositions.
Examples of such dispersants are succinimides and Mannich type.
References to these preparations are U.S. Pat. Nos. 4,259,194,
4,259,195, 4,265,773, 4,265,843, 4,727,387, 4,283,295, and
4,285,822.
In one embodiment, the molybdenum amine is a molybdenum-succinimide
complex. Suitable molybdenum-succinimide complexes are described,
for example, in U.S. Pat. No. 8,076,275. These complexes are
prepared by a process comprising reacting an acidic molybdenum
compound with an alkyl or alkenyl succinimide of a polyamine of
structure (III) or (IV) or mixtures thereof:
##STR00003## wherein R is a C.sub.24 to C.sub.350 (e.g., C.sub.70
to C.sub.128) alkyl or alkenyl group; R' is a straight or
branched-chain alkylene group having 2 to 3 carbon atoms; x is 1 to
11; and y is 1 to 10.
The molybdenum compounds used to prepare the molybdenum-succinimide
complex are acidic molybdenum compounds or salts of acidic
molybdenum compounds. By "acidic" is meant that the molybdenum
compounds will react with a basic nitrogen compound as measured by
ASTM D664 or D2896. Generally, the acidic molybdenum compounds are
hexavalent. Representative examples of suitable molybdenum
compounds include molybdenum trioxide, molybdic acid, ammonium
molybdate, sodium molybdate, potassium molybdate and other alkaline
metal molybdates and other molybdenum salts such as hydrogen salts,
(e.g., hydrogen sodium molybdate), MoOCl.sub.4, MoO.sub.2Br.sub.2,
Mo.sub.2O.sub.3Cl.sub.6, and the like.
The succinimides that can be used to prepare the
molybdenum-succinimide complex are disclosed in numerous references
and are well known in the art. Certain fundamental types of
succinimides and the related materials encompassed by the term of
art "succinimide" are taught in U.S. Pat. Nos. 3,172,892;
3,219,666; and 3,272,746. The term "succinimide" is understood in
the art to include many of the amide, imide, and amidine species
which may also be formed. The predominant product however is a
succinimide and this term has been generally accepted as meaning
the product of a reaction of an alkyl or alkenyl substituted
succinic acid or anhydride with a nitrogen-containing compound.
Preferred succinimides are those prepared by reacting a
polyisobutenyl succinic anhydride of about 70 to 128 carbon atoms
with a polyalkylene polyamine selected from triethylenetetramine,
tetraethylenepentamine, and mixtures thereof.
The molybdenum-succinimide complex may be post-treated with a
sulfur source at a suitable pressure and a temperature not to
exceed 120.degree. C. to provide a sulfurized
molybdenum-succinimide complex. The sulfurization step may be
carried out for a period of from about 0.5 to 5 hours (e.g., 0.5 to
2 hours). Suitable sources of sulfur include elemental sulfur,
hydrogen sulfide, phosphorus pentasulfide, organic polysulfides of
formula R.sub.2S.sub.x where R is hydrocarbyl (e.g., C.sub.1 to
C.sub.10 alkyl) and x is at least 3, C.sub.1 to C.sub.10
mercaptans, inorganic sulfides and polysulfides, thioacetamide, and
thiourea.
The lubricating oil compositions of the present invention will
contain at least about 0.0050 wt. %, at least about 0.0060 wt. %,
at least about 0.0070 wt. %, at least about 0.080 wt. %, at least
about 0.0090 wt. %, at least about 0.010 wt. %, at least about
0.011 wt. % of molybdenum, based upon the total mass of the
composition, provided from the one or more oil-soluble or dispersed
oil-stable molybdenum-containing compounds. In one embodiment, the
lubricating oil compositions of the present invention will contain
about 0.0050 wt. % to about 0.10 wt. %, about 0.0050 wt. % to about
0.050 wt. %, about 0.0050 wt. % to about 0.040 wt. %, about 0.0060
wt. % to about 0.030 wt. %, about 0.0080 wt. % to about 0.020 wt.
%, about 0.010 wt. % to about 0.018 wt. % of molybdenum, based on
the total mass of the composition provided from the one or more
oil-soluble or dispersed oil-stable molybdenum-containing
compounds.
The Dispersed Alkali Metal Borate Compound
The hydrated particulate alkali metal borates are well known in the
art and are available commercially. Representative examples of
hydrated particulate alkali metal borates and methods of
manufacture include those disclosed in, e.g., U.S. Pat. Nos.
3,313,727; 3,819,521; 3,853,772; 3,907,601; 3,997,454; 4,089,790;
6,737,387 and 6,534,450, the contents of which are incorporated
herein by reference. The hydrated alkali metal borates can be
represented by the following Formula:
M.sub.2O.mB.sub.2O.sub.3.nH.sub.2O where M is an alkali metal of
atomic number in the range of about 11 to about 19, e.g., sodium
and potassium; m is a number from about 2.5 to about 4.5 (both
whole and fractional); and n is a number from about 1.0 to about
4.8. The hydrated borate particles generally have a mean particle
size of less than about 1 micron.
The lubricating oil compositions of the present invention will
contain greater than about 50 ppm of boron, based upon the total
mass of the composition, provided from the one or more alkali metal
borate compounds. In one embodiment, the lubricating oil
compositions of the present invention will contain at least about
0.0060 wt. % of boron, based upon the total mass of the
composition, provided from the one or more alkali metal borate
compounds. In another embodiment, the lubricating oil compositions
of the present invention will contain at least about 0.0070 wt. %
of boron, based upon the total mass of the composition, provided
from the one or more alkali metal borate compounds. In yet another
embodiment, the lubricating oil compositions of the present
invention will contain at least about 0.0080 wt. % of boron, based
upon the total mass of the composition, provided from the one or
more alkali metal borate compounds. In yet another embodiment, the
lubricating oil compositions of the present invention will contain
at least about 0.010 wt. % of boron, based upon the total mass of
the composition, provided from the one or more alkali metal borate
compounds. In yet another embodiment, the lubricating oil
compositions of the present invention will contain at least about
0.0080 wt. % of boron, based upon the total mass of the
composition, provided from the one or more alkali metal borate
compounds. In other embodiments, the lubricating oil compositions
of the present invention will contain from about 0.0050 wt. % to no
more than about 0.20 wt. %, about 0.0050 wt. % to no more than
about 0.15 wt. %, about 0.0050 wt. % to no more than about 0.10 wt.
% about 0.0050 wt. % to no more than about 0.060 wt. %, about 0.010
wt. % to no more than about 0.15 wt. %, about 0.010 wt. % to no
more than about 0.12 wt. %, about 0.010 wt. % to no more than about
0.10 wt. %, about 0.010 wt. % to no more than about 0.060 wt. %,
based upon the total mass of the composition, provided from the one
or more alkali metal borate compounds.
In one aspect of this disclosure, the alkali metal borates employed
in this invention provides from 0.0050 to 0.060 wt. % of alkali
metal to the lubricating oil composition. In other embodiments, the
lubricating oil compositions of the present invention will contain
from about 0.0050 wt. % to no more than about 0.050 wt. %, about
0.010 wt. % to no more than about 0.050 wt. %, about 0.010 wt. % to
no more than 0.040 wt. %, about 0.010 wt. % to no more than 0.030
wt. %, based upon the total mass of the composition, provided from
the one or more alkali metal borated compounds.
In one aspect of this disclosure, the alkali metal borates employed
in this invention are present at ratios of boron to alkali metal in
the range from about 2.5:1 to about 4.5:1.
Oil dispersions of hydrated alkali metal borates are generally
prepared by forming, in deionized water, a solution of alkali metal
hydroxide and boric acid, optionally in the presence of a small
amount of the corresponding alkali metal carbonate. The solution is
then added to a lubricant composition comprising an oil of
lubricating viscosity, a dispersant and any additives to be
included therein (e.g., a detergent, or other optional additives)
to form an emulsion that is then dehydrated.
Because of their retention of hydroxyl groups on the borate
complex, these complexes are referred to as "hydrated alkali metal
borates" and compositions containing oil/water emulsions of these
hydrated alkali metal borates are referred to as "oil dispersions
of hydrated alkali metal borates".
In another aspect of this disclosure, the hydrated alkali metal
borate particles generally will have a mean particle size of less
than 1 micron. In this regard, it has been found that the hydrated
alkali metal borates employed in this invention preferably will
have a particle size where 90% or greater of the particles are less
than 0.6 microns.
In the oil dispersion of hydrated alkali metal borate, the hydrated
alkali metal borate will generally comprise about 10 to 75 weight
percent, preferably 25 to 50 weight percent, more preferably about
30 to 40 weight percent of the total weight of the oil dispersion
of the hydrated borate. (Unless otherwise stated, all percentages
are in weight percent.) This composition or concentrate is
employed, often in the form of an additive package, to form the
finished lubricant composition. Sufficient amounts of the
concentrate are added so that the finished lubricant composition
preferably comprises from about 0.2 to about 5 weight percent of
the total weight of the lubricant composition and, even more
preferably, from about 0.5 to 2 weight percent.
The lubricating oil compositions of the present invention will
contain greater than about 0.0050 wt. % of boron, based upon the
total mass of the composition, provided from the one or more alkali
metal borates. In some embodiments, the lubricating oil
compositions of the present invention will contain from about
0.0050 wt. % to about 0.050 wt. %, about 0.0050 wt. % to about
0.040 wt. %, about 0.0050 wt. % to about 0.030 wt. %, about 0.0075
wt. % to about 0.025 wt. % of boron, based upon the total mass of
the composition, provided from the one or more alkali metal
borates.
Sulfur Phosphorus Anti-Wear Compound
In one embodiment, the sulfur phosphorus anti-wear compound is zinc
dihydrocarbyl dithiophosphate (ZDDP).
Antiwear agents reduce wear of metal parts. Suitable anti-wear
agents include dihydrocarbyl dithiophosphate metal salts such as
zinc dihydrocarbyl dithiophosphates (ZDDP) of formula (V):
Zn[S--P(.dbd.S)(OR.sup.1)(OR.sup.2)].sub.2 (V)
wherein R.sup.1 and R.sup.2 may be the same of different
hydrocarbyl radicals having from 1 to 18 (e.g., 2 to 12) carbon
atoms and including radicals such as alkyl, alkenyl, aryl,
arylalkyl, alkaryl and cycloaliphatic radicals. Particularly
preferred as R.sup.1 and R.sup.2 groups are alkyl groups having
from 2 to 8 carbon atoms (e.g., the alkyl radicals may be ethyl,
n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl,
isopentyl, n-hexyl, isohexyl, 2-ethylhexyl). In order to obtain oil
solubility, the total number of carbon atoms (i.e.,
R.sup.1+R.sup.2) will be at least 5. The zinc dihydrocarbyl
dithiophosphate can therefore comprise zinc dialkyl
dithiophosphates. The zinc dialkyl dithiophosphate can be a primary
or secondary zinc dialkyl dithiophosphate.
ZDDP may be present at 3 wt. % or less (e.g., 0.1 to 1.5 wt. %, or
0.5 to 1.0 wt. %) of the lubricating oil composition.
In some embodiments, ZDDP provides from 0 to 0.06 wt. % phosphorus
to the lubricating oil composition. In other embodiments, ZDDP
provides from 0 to 0.05 wt. %, from 0 to 0.04 wt. %, from 0 to 0.03
wt. %, from 0 to 0.02 wt. %, from 0 to 0.01 wt. %, from 0 to 0.009,
from 0 to 0.006, from 0 to 0.004, from 0 to 0.002, wt. %, 0 wt. %
phosphorus to the lubricating oil composition.
In some embodiments, ZDDP provides from 0 to 0.12 wt. % sulfur to
the lubricating oil composition, based on the weight of the
lubricating oil composition. In other embodiments, ZDDP provides
from 0 to 0.10 wt. %, from 0 to 0.08 wt. %, from 0 to 0.06 wt. %,
from 0 to 0.04 wt. %, from 0 to 0.02 wt. %, from 0 to 0.018, from 0
to 0.012, from 0 to 0.008, from 0 to 0.004, wt. %, 0 wt. % sulfur
to the lubricating oil composition, based on the weight of the
lubricating oil composition.
Nitrogen Containing Dispersant
Dispersants maintain in suspension materials resulting from
oxidation during engine operation that are insoluble in oil, thus
preventing sludge flocculation and precipitation or deposition on
metal parts. Dispersants useful herein include nitrogen-containing,
ashless (metal-free) dispersants known to effective to reduce
formation of deposits upon use in gasoline and diesel engines.
Suitable dispersants include hydrocarbyl succinimides, hydrocarbyl
succinamides, mixed ester/amides of hydrocarbyl-substituted
succinic acid, hydroxyesters of hydrocarbyl-substituted succinic
acid, and Mannich condensation products of hydrocarbyl-substituted
phenols, formaldehyde and polyamines. Also suitable are
condensation products of polyamines and hydrocarbyl-substituted
phenyl acids. Mixtures of these dispersants can also be used.
Basic nitrogen-containing ashless dispersants are well-known
lubricating oil additives and methods for their preparation are
extensively described in the patent literature. Preferred
dispersants are the alkenyl succinimides and succinamides where the
alkenyl-substituent is a long-chain of preferably greater than 40
carbon atoms. These materials are readily made by reacting a
hydrocarbyl-substituted dicarboxylic acid material with a molecule
containing amine functionality. Examples of suitable amines are
polyamines such as polyalkylene polyamines, hydroxy-substituted
polyamines and polyoxyalkylene polyamines.
Particularly preferred ashless dispersants are the polyisobutenyl
succinimides formed from polyisobutenyl succinic anhydride and a
polyalkylene polyamine such as a polyethylene polyamine of formula:
NH.sub.2(CH.sub.2CH.sub.2NH).sub.zH wherein z is 1 to 11. The
polyisobutenyl group is derived from polyisobutene and preferably
has a number average molecular weight (M.sub.n) in a range of 700
to 3000 Daltons (e.g., 900 to 2500 Daltons). For example, the
polyisobutenyl succinimide may be a bis-succinimide derived from a
polyisobutenyl group having a M.sub.n of 900 to 2500 Daltons.
As is known in the art, the dispersants may be post-treated (e.g.,
with a boronating agent or a cyclic carbonate).
Nitrogen-containing ashless (metal-free) dispersants are basic, and
contribute to the TBN of a lubricating oil composition to which
they are added, without introducing additional sulfated ash.
Dispersants may be present at 0.1 to 10 wt. % (e.g., 2 to 5, wt. %)
of the lubricating oil composition.
Nitrogen from the dispersants is present from greater than 0.0050
to 0.30 wt. % (e.g., greater than 0.0050 to 0.10 wt. %, 0.0050 to
0.080 wt. %, 0.0050 to 0.060 wt. %, 0.0050 to 0.050 wt. %, 0.0050
to 0.040 wt. %, 0.0050 to 0.030 wt. %,) based on the weight of the
dispersants in the finished oil.
Detergents
The lubricating oil composition of the present invention can
further contain one or more detergents.
Detergents that may be used include oil-soluble overbased
sulfonate, non-sulfur containing phenate, sulfurized phenates,
salixarate, salicylate, saligenin, complex detergents and
naphthenate detergents and other oil-soluble alkylhydroxybenzoates
of a metal, particularly the alkali or alkaline earth metals, e.g.,
barium, sodium, potassium, lithium, calcium, and magnesium. The
most commonly used metals are calcium and magnesium, which may
present separately or in combination in detergents used in a
lubricant.
In some embodiments, the detergent is a calcium detergent. In one
embodiment, the calcium-containing detergent may be used in an
amount that provides from 0.14 to 0.30 wt. % calcium to the
lubricating oil composition. In other embodiment, the
calcium-containing detergent may be used in an amount that provides
from 0.15 to 0.28 wt. % calcium to the lubricating oil
composition.
In other embodiments, the detergent is a magnesium detergent. In
one embodiment, the magnesium-containing detergent may be used in
an amount that provides from 0.0005 to 0.060 wt. % magnesium to the
lubricating oil composition. In some embodiments, the
magnesium-containing detergent may be used in an amount that
provides from 0.0005 to 0.050, 0.001 to 0.050, 0.001 to 0.040 wt. %
magnesium to the lubricating oil composition.
Overbased metal detergents are generally produced by carbonating a
mixture of hydrocarbons, detergent acid, for example: sulfonic
acid, alkylhydroxybenzoate etc., metal oxide or hydroxides (for
example calcium oxide or calcium hydroxide) and promoters such as
xylene, methanol and water. For example, for preparing an overbased
calcium sulfonate, in carbonation, the calcium oxide or hydroxide
reacts with the gaseous carbon dioxide to form calcium carbonate.
The sulfonic acid is neutralized with an excess of CaO or
Ca(OH).sub.2, to form the sulfonate.
Overbased detergents may be low overbased, e.g., an overbased salt
having a TBN below 100 on an actives basis. In one embodiment, the
TBN of a low overbased salt may be from about 30 to about 100. In
another embodiment, the TBN of a low overbased salt may be from
about 30 to about 80. Overbased detergents may be medium overbased,
e.g., an overbased salt having a TBN from about 100 to about 250.
In one embodiment, the TBN of a medium overbased salt may be from
about 100 to about 200. In another embodiment, the TBN of a medium
overbased salt may be from about 125 to about 175. Overbased
detergents may be high overbased, e.g., an overbased salt having a
TBN above 250. In one embodiment, the TBN of a high overbased salt
may be from about 250 to about 800 on an actives basis.
Generally, the amount of the detergent can be from about 0.001 wt.
% to about 50 wt. %, or from about 0.05 wt. % to about 25 wt. %, or
from about 0.1 wt. % to about 20 wt. %, or from about 0.01 to 15
wt. % based on the total weight of the lubricating oil
composition.
In general, the level of sulfur in the lubricating oil compositions
of the present invention is less than or equal to about 0.30 wt.,
based on the total weight of the lubricating oil composition, e.g.,
a level of sulfur of about 0.01 to about 0.30 wt. %, about 0.01 to
about 0.25 wt. %, about 0.01 to about 0.24 wt. %, about 0.01 to
about 0.23 wt. %, about 0.01 to about 0.22 wt. %, about 0.01 to
about 0.21 wt. %, about 0.01 to about 0.20 wt. %, about 0.01 to
about 0.19 wt. %, about 0.01 to about 0.18 wt. %, about 0.01 to
about 0.17 wt. %, about 0.01 to about 0.16 wt. %, of sulfur based
on the total weight of the lubricating oil composition.
In some embodiments, the lubricating oil compositions of the
present invention are substantially free of any phosphorus content.
In some embodiments, the level of phosphorous in the lubricating
oil compositions of the present invention is from about 0.005 wt. %
to about 0.06 wt. %, 0.010 wt. % to about 0.06 wt. %, 0.010 wt. %
to about 0.055 wt. %, 0.010 wt. % to about 0.05 wt. %, 0.010 wt. %
to about 0.05 wt. %, 0.010 wt. % to about 0.045 wt. %, 0.010 wt. %
to about 0.04 wt. %, 0.010 wt. % to about 0.035 wt. %, 0.010 wt. %
to about 0.03 wt. %, based on the total weight of the lubricating
oil composition. In one embodiment, the lubricating oil
compositions of the present invention are substantially free of any
zinc dialkyl dithiophosphate.
In one embodiment, the level of sulfated ash produced by the
lubricating oil compositions of the present invention is less than
or equal to about 1.1 wt. % as determined by ASTM D 874, e.g., a
level of sulfated ash of from about 0.6 to about 1.1 wt. % as
determined by ASTM D 874. In one embodiment, the level of sulfated
ash produced by the lubricating oil compositions of the present
invention is less than or equal to about 1.0 wt. % as determined by
ASTM D 874, e.g., a level of sulfated ash of from about 0.6 to
about 1.0 wt. % as determined by ASTM D 874. In one embodiment, the
level of sulfated ash produced by the lubricating oil compositions
of the present invention is less than or equal to about 0.9 wt. %
as determined by ASTM D 874, e.g., a level of sulfated ash of from
about 0.6 to about 0.9 wt. % as determined by ASTM D 874, based on
the total weight of the lubricating oil composition.
Other Lubricating Oil Additives
The lubricating oil compositions of the present disclosure may also
contain other conventional additives that can impart or improve any
desirable property of the lubricating oil composition in which
these additives are dispersed or dissolved. Any additive known to a
person of ordinary skill in the art may be used in the lubricating
oil compositions disclosed herein. Some suitable additives have
been described in Mortier et al., "Chemistry and Technology of
Lubricants", 2nd Edition, London, Springer, (1996); and Leslie R.
Rudnick, "Lubricant Additives: Chemistry and Applications", New
York, Marcel Dekker (2003), both of which are incorporated herein
by reference. For example, the lubricating oil compositions can be
blended with antioxidants, anti-wear agents, additional metal
detergents, rust inhibitors, dehazing agents, demulsifying agents,
metal deactivating agents, friction modifiers, pour point
depressants, antifoaming agents, co-solvents, corrosion-inhibitors,
additional ashless dispersants, multifunctional agents, dyes,
extreme pressure agents and the like and mixtures thereof. A
variety of the additives are known and commercially available.
These additives, or their analogous compounds, can be employed for
the preparation of the lubricating oil compositions of the
disclosure by the usual blending procedures.
Friction Modifiers
The lubricating oil composition of the present invention can
contain one or more friction modifiers that can lower the friction
between moving parts. Any friction modifier known by a person of
ordinary skill in the art may be used in the lubricating oil
composition. Non-limiting examples of suitable friction modifiers
include fatty carboxylic acids; derivatives (e.g., alcohol, esters,
borated esters, amides, metal salts and the like) of fatty
carboxylic acid; mono-, di- or tri-alkyl substituted phosphoric
acids or phosphonic acids; derivatives (e.g., esters, amides, metal
salts and the like) of mono-, di- or tri-alkyl substituted
phosphoric acids or phosphonic acids; mono-, di- or tri-alkyl
substituted amines; mono- or di-alkyl substituted amides and
combinations thereof. In some embodiments examples of friction
modifiers include, but are not limited to, alkoxylated fatty
amines; borated fatty epoxides; fatty phosphites, fatty epoxides,
fatty amines, borated alkoxylated fatty amines, metal salts of
fatty acids, fatty acid amides, glycerol esters, borated glycerol
esters; and fatty imidazolines as disclosed in U.S. Pat. No.
6,372,696, the contents of which are incorporated by reference
herein; friction modifiers obtained from a reaction product of a
C.sub.4 to C.sub.75, or a C.sub.6 to C.sub.24, or a C.sub.6 to
C.sub.20, fatty acid ester and a nitrogen-containing compound
selected from the group consisting of ammonia, and an alkanolamine
and the like and mixtures thereof. The amount of the friction
modifier may vary from about 0.01 wt. % to about 10 wt. %, from
about 0.05 wt. % to about 5 wt. %, or from about 0.1 wt. % to about
3 wt. %, based on the total weight of the lubricating oil
composition.
Antioxidants
Antioxidants reduce the tendency of mineral oils during to
deteriorate during service. Oxidative deterioration can be
evidenced by sludge in the lubricant, varnish-like deposits on the
metal surfaces, and by viscosity growth. Suitable antioxidants
include hindered phenols, aromatic amines, and sulfurized
alkylphenols and alkali and alkaline earth metals salts
thereof.
Examples of the hindered phenol oxidation inhibitors include
2,6-di-t-butyl-p-cresol, 4,4'-methylenebis(2,6-di-t-butylphenol),
4,4'-methylenebis(6-t-butyl-o-cresol),
4,4'-isopropylidenebis(2,6-di-t-butylphenol),
4,4'-bis(2,6-di-t-butylphenol),
2,2'-methylenebis(4-methyl-6-t-butylphenol),
4,4'-thiobis(2-methyl-6-t-butylphenol),
2,2-thio-diethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate],
octyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, octadecyl
3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, and octyl
3-(3,54-butyl-4-hydroxy-3-methylphenyl)propionate, and commercial
products such as, but not limited to, Irganox L135.RTM. (BASF),
Naugalube 531.RTM. (Chemtura), and Ethanox 376.RTM. (SI Group).
The lubricating oil compositions of the present invention can
contain an amine antioxidant. In one embodiment, the antioxidant is
a diphenylamine antioxidant. Examples of diphenyl amine
antioxidants include monoalkylated diphenylamine, dialkylated
diphenylamine, trialkylated diphenylamine, and mixtures thereof.
Some of these include butyldiphenylamine, di-butyldiphenylamine,
oxtyldiphenylamine, di-octyldiphenylamine, nonyldiphenylamine,
di-nonyldiphenylamine, t-butyl-t-octyldiphenylamine, bis-nonylated
diphenylamine, bis-octylated diphenylamine, and
phenyl-.alpha.-naphthylamine, alkyl or arylalkyl substituted
phenyl-.alpha.-naphthylamine, alkylated p-phenylene diamines,
tetramethyl-diaminodiphenylamine and the like.
Antioxidants may be present at 0.01 to 5 wt. % (e.g., 0.1 to 2 wt.
%) of the lubricating oil composition.
Corrosion Inhibitors
Corrosion inhibitors protect lubricated metal surfaces against
chemical attack by water or other contaminants. Suitable corrosion
inhibitors include polyoxyalkylene polyols and esters thereof,
polyoxyalkylene phenols, thiadiazoles and anionic alkyl sulfonic
acids. Such additives may be present at 0.01 to 5 wt. % (e.g., 0.1
to 1.5 wt. %) of the lubricating oil composition.
Foam Inhibitors
Foam control can be provided by many compounds including a foam
inhibitor of the polysiloxane type (e.g., silicone oil or
polydimethyl siloxane). Foam inhibitors may be present at less than
0.1 wt. % (e.g., 0.0001 to 0.01 wt. %) of the lubricating oil
composition.
Pour Point Depressants
Pour point depressants lower the minimum temperature at which a
fluid will flow or can be poured. Suitable pour point depressants
include C.sub.8 to C.sub.18 dialkyl fumarate/vinyl acetate
copolymers, polyalkylmethacrylates and the like. Such additives may
be present at 0.01 to 5 wt. % (e.g., 0.1 to 1.5 wt. %) of the
lubricating oil composition.
Viscosity Modifiers
The lubricating oil composition can further comprise a viscosity
modifier.
Viscosity modifiers function to impart high and low temperature
operability to a lubricating oil. The viscosity modifier used may
have that sole function or may be multifunctional. Multifunctional
viscosity modifiers that also function as dispersants are also
known. Suitable viscosity modifiers include polyisobutylene,
copolymers of ethylene and propylene and higher alpha-olefins,
polymethacrylates, polyalkylmethacrylates, methacrylate copolymers,
copolymers of an unsaturated dicarboxylic acid and a vinyl
compound, interpolymers of styrene and acrylic esters, and
partially hydrogenated copolymers of styrene/isoprene,
styrene/butadiene, and isoprene/butadiene, as well as the partially
hydrogenated homopolymers of butadiene and isoprene and
isoprene/divinylbenzene. In one embodiment, the viscosity modifier
is a polyalkylmethacrylate. The topology of the viscosity modifier
could include, but is not limited to, linear, branched,
hyperbranched, star, or comb topology. The viscosity modifier can
be non-dispersant type or dispersant type. In one embodiment, the
viscosity modifier is a dispersant polymethacrylate.
Suitable viscosity modifiers have a Permanent Shear Stability Index
(PSSI) of 30 or less (e.g., 10 or less, 5 or less, or even 2 or
less). PSSI is a measure of the irreversible decrease, resulting
from shear, in an oil's viscosity contributed by an additive. PSSI
is determined according to ASTM D6022. The lubricating oil
compositions of the present disclosure display stay-in-grade
capability. Retention of kinematic viscosity at 100.degree. C.
within a single SAE viscosity grade classification by a fresh oil
and its sheared version is evidence of an oil's stay-in-grade
capability.
The viscosity modifier may be used in an amount of from 0.5 to 15.0
wt. % (e.g., 0.5 to 10 wt. %, 0.5 to 5 wt. %, 1.0 to 15 wt. %, 1.0
to 10 wt. %, or 1.0 to 5 wt. %), based on the total weight of the
lubricating oil composition.
In general, the concentration of each of the additives in the
lubricating oil composition, when used, may range from about 0.001
wt. % to about 20 wt. %, from about 0.01 wt. % to about 15 wt. %,
or from about 0.1 wt. % to about 10 wt. %, from about 0.005 wt. %
to about 5 wt. %, or from about 0.1 wt. % to about 2.5 wt. %, based
on the total weight of the lubricating oil composition. Further,
the total amount of the additives in the lubricating oil
composition may range from about 0.001 wt. % to about 20 wt. %,
from about 0.01 wt. % to about 10 wt. %, or from about 0.1 wt. % to
about 5 wt. %, based on the total weight of the lubricating oil
composition.
In the preparation of lubricating oil formulations, it is common
practice to introduce the additives in the form of 10 to 80 wt. %
active ingredient concentrates in hydrocarbon oil, e.g. mineral
lubricating oil, or other suitable solvent.
Usually these concentrates may be diluted with 3 to 100, e.g., 5 to
40, parts by weight of lubricating oil per part by weight of the
additive package in forming finished lubricants, e.g. crankcase
motor oils. The purpose of concentrates, of course, is to make the
handling of the various materials less difficult and awkward as
well as to facilitate solution or dispersion in the final
blend.
Processes of Preparing Lubricating Oil Compositions
The lubricating oil compositions disclosed herein can be prepared
by any method known to a person of ordinary skill in the art for
making lubricating oils. In some embodiments, the base oil can be
blended or mixed with the additive compounds described herein. Any
mixing or dispersing equipment known to a person of ordinary skill
in the art may be used for blending, mixing or solubilizing the
ingredients. The blending, mixing or solubilizing may be carried
out with a blender, an agitator, a disperser, a mixer (e.g.,
planetary mixers and double planetary mixers), a homogenizer (e.g.,
Gaulin homogenizers and Rannie homogenizers), a mill (e.g., colloid
mill, ball mill and sand mill) or any other mixing or dispersing
equipment known in the art.
In some embodiments, the lubricating oil composition disclosed
herein may be suitable for use as motor oils (that is, engine oils
or crankcase oils), in a compression ignited engine or in a
spark-ignited internal combustion engine, particularly a direct
injected, boosted, engine.
The following examples are presented to exemplify embodiments of
the disclosure but are not intended to limit the disclosure to the
specific embodiments set forth. Unless indicated to the contrary,
all parts and percentages are by weight. All numerical values are
approximate. When numerical ranges are given, it should be
understood that embodiments outside the stated ranges may still
fall within the scope of the disclosure. Specific details described
in each example should not be construed as necessary features of
the disclosure.
It will be understood that various modifications may be made to the
embodiments disclosed herein. Therefore, the above description
should not be construed as limiting, but merely as exemplifications
of preferred embodiments. For example, the functions described
above and implemented as the best mode for operating the present
disclosure are for illustration purposes only. Other arrangements
and methods may be implemented by those skilled in the art without
departing from the scope and spirit of this disclosure. Moreover,
those skilled in the art will envision other modifications within
the scope and spirit of the claims appended hereto.
EXAMPLES
The following examples are intended for illustrative purposes only
and do not limit in any way the scope of the present
disclosure.
Reference Example 1
A 10W-30 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Example 1 is 0.028 wt. % (2) a
mixture of calcium phenate, sulfonate and salicylate detergents in
an amount to provide the calcium content provided in table 2; (3) a
primary ZnDTP in an amount to provide the phosphorus content
provided in table 2; (4) a molybdenum succinimide antioxidant in an
amount to provide the molybdenum content provided in table 2; (5) a
hydrated potassium borate dispersion in an amount to provide the
potassium content provided in table 2; (6) an alkylated
diphenylamine; (7) 5 ppm in terms of silicon content, of a foam
inhibitor; (8) an ethylene propylene viscosity modifier in an
amount to give the proper viscosity grade; and (9) a
polymethacrylate PPD (10) the remainder, a Group I base oil.
Example 2
A 5W-30 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Example 2 is 0.028 wt. % (2) a
mixture of calcium phenate, sulfonate and salicylate detergents in
an amount to provide the calcium content provided in table 2; (3) a
primary ZnDTP in an amount to provide the phosphorus content
provided in table 2; (4) a molybdenum succinimide antioxidant in an
amount to provide the molybdenum content provided in table 2; (5) a
hydrated potassium borate dispersion in an amount to provide the
potassium content provided in table 2; (6) an alkylated
diphenylamine; (7) 5 ppm in terms of silicon content, of a foam
inhibitor; (8) an ethylene propylene viscosity modifier in an
amount to give the proper viscosity grade; and (9) a
polymethacrylate PPD (10) the remainder, a Group III base oil.
Example 3
A 0W-30 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Example 3 is 0.028 wt. % (2) a
mixture of calcium phenate, sulfonate and salicylate detergents in
an amount to provide the calcium content provided in table 2; (3) a
primary ZnDTP in an amount to provide the phosphorus content
provided in table 2; (4) a molybdenum succinimide antioxidant in an
amount to provide the molybdenum content provided in table 2; (5) a
hydrated potassium borate dispersion in an amount to provide the
potassium content provided in table 2; (6) an alkylated
diphenylamine; (7) 5 ppm in terms of silicon content, of a foam
inhibitor; (8) an ethylene propylene viscosity modifier in an
amount to give the proper viscosity grade; and (9) a
polymethacrylate PPD (10) the remainder, a Group III base oil.
Example 4
A 5W-20 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Example 4 is 0.028 wt. % (2) a
mixture of calcium phenate, sulfonate and salicylate detergents in
an amount to provide the calcium content provided in table 2; (3) a
primary ZnDTP in an amount to provide the phosphorus content
provided in table 2; (4) a molybdenum succinimide antioxidant in an
amount to provide the molybdenum content provided in table 2; (5) a
hydrated potassium borate dispersion in an amount to provide the
potassium content provided in table 2; (6) an alkylated
diphenylamine; (7) 5 ppm in terms of silicon content, of a foam
inhibitor; (8) an ethylene propylene viscosity modifier in an
amount to give the proper viscosity grade; and (9) a
polymethacrylate PPD (10) the remainder, a Group III base oil.
Example 5
A 0W-20 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Example 5 is 0.028 wt. % (2) a
mixture of calcium phenate, sulfonate and salicylate detergents in
an amount to provide the calcium content provided in table 2; (3) a
primary ZnDTP in an amount to provide the phosphorus content
provided in table 2; (4) a molybdenum succinimide antioxidant in an
amount to provide the molybdenum content provided in table 2; (5) a
hydrated potassium borate dispersion in an amount to provide the
potassium content provided in table 2; (6) an alkylated
diphenylamine; (7) 5 ppm in terms of silicon content, of a foam
inhibitor; (8) an ethylene propylene viscosity modifier in an
amount to give the proper viscosity grade; and (9) a
polymethacrylate PPD (10) the remainder, a Group III base oil.
Example 6
A 0W-20 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Example 6 is 0.028 wt. % (2) a
mixture of calcium phenate, sulfonate and salicylate detergents in
an amount to provide the calcium content provided in table 2; (3) a
primary ZnDTP in an amount to provide the phosphorus content
provided in table 2; (4) a molybdenum succinimide antioxidant in an
amount to provide the molybdenum content provided in table 2; (5) a
hydrated potassium borate dispersion in an amount to provide the
potassium content provided in table 2; (6) an alkylated
diphenylamine; (7) 5 ppm in terms of silicon content, of a foam
inhibitor; (8) an ethylene propylene viscosity modifier in an
amount to give the proper viscosity grade; and (9) a
polymethacrylate PPD (10) the remainder, a Group III base oil.
Example 7
A 0W-16 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Example 7 is 0.028 wt. % (2) a
mixture of calcium phenate, sulfonate and salicylate detergents in
an amount to provide the calcium content provided in table 2; (3) a
primary ZnDTP in an amount to provide the phosphorus content
provided in table 2; (4) a molybdenum succinimide antioxidant in an
amount to provide the molybdenum content provided in table 2; (5) a
hydrated potassium borate dispersion in an amount to provide the
potassium content provided in table 2; (6) an alkylated
diphenylamine; (7) 5 ppm in terms of silicon content, of a foam
inhibitor; (8) an ethylene propylene viscosity modifier in an
amount to give the proper viscosity grade; and (9) a
polymethacrylate PPD (10) the remainder, a Group III base oil.
Example 8
A 0W-16 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Example 8 is 0.028 wt. % (2) a
mixture of calcium phenate, sulfonate and salicylate detergents in
an amount to provide the calcium content provided in table 2; (3) a
primary ZnDTP in an amount to provide the phosphorus content
provided in table 2; (4) a molybdenum succinimide antioxidant in an
amount to provide the molybdenum content provided in table 2; (5) a
hydrated potassium borate dispersion in an amount to provide the
potassium content provided in table 2; (6) an alkylated
diphenylamine; (7) 5 ppm in terms of silicon content, of a foam
inhibitor; (8) an ethylene propylene viscosity modifier in an
amount to give the proper viscosity grade; and (9) a
polymethacrylate PPD (10) the remainder, a Group III base oil.
Example 9
A 0W-16 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Example 9 is 0.028 wt. % (2) a
mixture of calcium phenate, sulfonate and salicylate detergents in
an amount to provide the calcium content provided in table 2; (3) a
magnesium sulfonate detergent in an amount to provide the magnesium
content provided in table 2; (4) a primary ZnDTP in an amount to
provide the phosphorus content provided in table 2; (5) a
molybdenum succinimide antioxidant in an amount to provide the
molybdenum content provided in table 2; (6) a hydrated potassium
borate dispersion in an amount to provide the potassium content
provided in table 2; (7) an alkylated diphenylamine; (8) 5 ppm in
terms of silicon content, of a foam inhibitor; (9) an ethylene
propylene viscosity modifier in an amount to give the proper
viscosity grade; and (10) a polymethacrylate PPD (11) the
remainder, a Group III base oil.
Example 10
A 5W-30 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Example 10 is 0.028 wt. % (2) a
mixture of calcium phenate, sulfonate and salicylate detergents in
an amount to provide the calcium content provided in table 2; (3) a
primary ZnDTP in an amount to provide the phosphorus content
provided in table 2; (4) a molybdenum succinimide antioxidant in an
amount to provide the molybdenum content provided in table 2; (5) a
hydrated potassium borate dispersion in an amount to provide the
potassium content provided in table 2; (6) an alkylated
diphenylamine; (7) 5 ppm in terms of silicon content, of a foam
inhibitor; (8) an ethylene propylene viscosity modifier in an
amount to give the proper viscosity grade; and (9) a
polymethacrylate PPD (10) the remainder, a Group III base oil.
Example 11
A 5W-30 lubricating oil composition which was zinc and phosphorus
free was prepared that contained a major amount of a base oil of
lubricating viscosity and the following additives: (1) an ethylene
carbonate post-treated bis-succinimide and a borated
bis-succinimide; Total Nitrogen content from the dispersants in
Example 11 is 0.028 wt. % (2) a mixture of calcium phenate,
sulfonate and salicylate detergents in an amount to provide the
calcium content provided in table 2; (3) a molybdenum succinimide
antioxidant in an amount to provide the molybdenum content provided
in table 2; (4) a hydrated potassium borate dispersion in an amount
to provide the potassium content provided in table 2; (5) an
alkylated diphenylamine; (6) 5 ppm in terms of silicon content, of
a foam inhibitor; (7) an ethylene propylene viscosity modifier in
an amount to give the proper viscosity grade; and (8) a
polymethacrylate PPD (9) the remainder, a Group III base oil.
Example 12
A 0W-20 lubricating oil composition which was zinc and phosphorus
free was prepared that contained a major amount of a base oil of
lubricating viscosity and the following additives: (1) an ethylene
carbonate post-treated bis-succinimide and a borated
bis-succinimide; Total Nitrogen content from the dispersants in
Example 12 is 0.028 wt. % (2) a mixture of calcium phenate,
sulfonate and salicylate detergents in an amount to provide the
calcium content provided in table 2; (3) a molybdenum succinimide
antioxidant in an amount to provide the molybdenum content provided
in table 2; (4) a hydrated potassium borate dispersion in an amount
to provide the potassium content provided in table 2; (5) an
alkylated diphenylamine; (6) 5 ppm in terms of silicon content, of
a foam inhibitor; (7) an ethylene propylene viscosity modifier in
an amount to give the proper viscosity grade; and (8) a
polymethacrylate PPD (9) the remainder, a Group III base oil.
Example 13
A 0W-20 lubricating oil composition which was zinc and phosphorus
free was prepared that contained a major amount of a base oil of
lubricating viscosity and the following additives: (1) an ethylene
carbonate post-treated bis-succinimide and a borated
bis-succinimide; Total Nitrogen content from the dispersants in
Example 13 is 0.028 wt. % (2) a mixture of calcium phenate,
sulfonate and salicylate detergents in an amount to provide the
calcium content provided in table 2; (3) a molybdenum succinimide
antioxidant in an amount to provide the molybdenum content provided
in table 2; (4) a hydrated potassium borate dispersion in an amount
to provide the potassium content provided in table 2; (5) an
alkylated diphenylamine; (6) 5 ppm in terms of silicon content, of
a foam inhibitor; (7) an ethylene propylene viscosity modifier in
an amount to give the proper viscosity grade; and (8) a
polymethacrylate PPD (9) the remainder, a Group III base oil.
Example 14
A 0W-20 lubricating oil composition which was zinc and phosphorus
free was prepared that contained a major amount of a base oil of
lubricating viscosity and the following additives: (1) an ethylene
carbonate post-treated bis-succinimide and a borated
bis-succinimide; Total Nitrogen content from the dispersants in
Example 14 is 0.028 wt. % (2) a mixture of calcium phenate,
sulfonate and salicylate detergents in an amount to provide the
calcium content provided in table 2; (3) a magnesium sulfonate
detergent in an amount to provide the magnesium content provided in
table 2; (4) a molybdenum succinimide antioxidant in an amount to
provide the molybdenum content provided in table 2; (5) a hydrated
potassium borate dispersion in an amount to provide the potassium
content provided in table 2; (6) an alkylated diphenylamine; (7) 5
ppm in terms of silicon content, of a foam inhibitor; (8) an
ethylene propylene viscosity modifier in an amount to give the
proper viscosity grade; and (9) a polymethacrylate PPD (10) the
remainder, a Group III base oil.
Comparative Example 1
A 0W-16 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Comparative Example 1 is 0.028 wt.
% (2) a mixture of calcium phenate, sulfonate and salicylate
detergents in an amount to provide the calcium content provided in
table 2; (3) a primary ZnDTP in an amount to provide the phosphorus
content provided in table 2; (4) an alkylated diphenylamine; (5) 5
ppm in terms of silicon content, of a foam inhibitor; (6) an
ethylene propylene viscosity modifier in an amount to give the
proper viscosity grade; and (7) a polymethacrylate PPD (8) the
remainder, a Group III base oil.
Comparative Example 2
A 0W-16 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Comparative Example 2 is 0.028 wt.
% (2) a mixture of calcium phenate, sulfonate and salicylate
detergents in an amount to provide the calcium content provided in
table 2; (3) a primary ZnDTP in an amount to provide the phosphorus
content provided in table 2; (4) a molybdenum succinimide
antioxidant in an amount to provide the molybdenum content provided
in table 2; (5) an alkylated diphenylamine; (6) 5 ppm in terms of
silicon content, of a foam inhibitor; (7) an ethylene propylene
viscosity modifier in an amount to give the proper viscosity grade;
and (8) a polymethacrylate PPD (9) the remainder, a Group III base
oil.
Comparative Example 3
A 0W-16 lubricating oil composition was prepared that contained a
major amount of a base oil of lubricating viscosity and the
following additives: (1) an ethylene carbonate post-treated
bis-succinimide and a borated bis-succinimide; Total Nitrogen
content from the dispersants in Comparative Example 3 is 0.028 wt.
% (2) a mixture of calcium phenate, sulfonate and salicylate
detergents in an amount to provide the calcium content provided in
table 2; (3) a primary ZnDTP in an amount to provide the phosphorus
content provided in table 2; (4) a hydrated potassium borate
dispersion in an amount to provide the potassium content provided
in table 2; (5) an alkylated diphenylamine; (6) 5 ppm in terms of
silicon content, of a foam inhibitor; (7) an ethylene propylene
viscosity modifier in an amount to give the proper viscosity grade;
and (8) a polymethacrylate PPD (9) the remainder, a Group III base
oil.
Comparative Example 4
A 5W-30 lubricating oil composition which was zinc and phosphorus
free was prepared that contained a major amount of a base oil of
lubricating viscosity and the following additives: (1) an ethylene
carbonate post-treated bis-succinimide and a borated
bis-succinimide; Total Nitrogen content from the dispersants in
Comparative Example 4 is 0.028 wt. % (2) a mixture of calcium
phenate, sulfonate and salicylate detergents in an amount to
provide the calcium content provided in table 2; (3) an alkylated
diphenylamine; (4) 5 ppm in terms of silicon content, of a foam
inhibitor; (5) an ethylene propylene viscosity modifier in an
amount to give the proper viscosity grade; and (6) a
polymethacrylate PPD (7) the remainder, a Group III base oil.
Comparative Example 5
A 5W-30 lubricating oil composition which was zinc and phosphorus
free was prepared that contained a major amount of a base oil of
lubricating viscosity and the following additives: (1) an ethylene
carbonate post-treated bis-succinimide and a borated
bis-succinimide; Total Nitrogen content from the dispersants in
Comparative Example 5 is 0.028 wt. % (2) a mixture of calcium
phenate, sulfonate and salicylate detergents in an amount to
provide the calcium content provided in table 2; (3) a molybdenum
succinimide antioxidant in an amount to provide the molybdenum
content provided in table 2; (4) an alkylated diphenylamine; (5) 5
ppm in terms of silicon content, of a foam inhibitor; (6) an
ethylene propylene viscosity modifier in an amount to give the
proper viscosity grade; and (7) a polymethacrylate PPD (8) the
remainder, a Group III base oil.
Comparative Example 6
A 5W-30 lubricating oil composition which was zinc and phosphorus
free was prepared that contained a major amount of a base oil of
lubricating viscosity and the following additives: (1) an ethylene
carbonate post-treated bis-succinimide and a borated
bis-succinimide; Total Nitrogen content from the dispersants in
Comparative Example 6 is 0.028 wt. % (2) a mixture of calcium
phenate, sulfonate and salicylate detergents in an amount to
provide the calcium content provided in table 2; (3) a hydrated
potassium borate dispersion in an amount to provide the potassium
content provided in table 2; (4) an alkylated diphenylamine; (5) 5
ppm in terms of silicon content, of a foam inhibitor; (6) an
ethylene propylene viscosity modifier in an amount to give the
proper viscosity grade; and (7) a polymethacrylate PPD (8) the
remainder, a Group III base oil.
Testing
The lubricating oil compositions were evaluated in the Komatsu Hot
Tube Test, the Engine Bench Test, and the Shell Four Ball Wear Test
to assess their performance.
Komatsu Hot Tube Test
Detergency and thermal and oxidative stability are performance
areas that are generally accepted in the industry as being
essential to satisfactory overall performance of a lubricating oil.
The Komatsu Hot Tube test is a lubrication industry bench test (JPI
5S-55-99) that measures the detergency and thermal and oxidative
stability of a lubricating oil. During the test, a specified amount
of test oil is pumped upwards through a glass tube that is placed
inside an oven set at a certain temperature. Air is introduced in
the oil stream before the oil enters the glass tube and flows
upward with the oil. Evaluations of the lubricating oils were
conducted at a temperature of 280.degree. C. The test result is
determined by comparing the amount of lacquer deposited on the
glass test tube to a rating scale ranging from 1.0 (very black) to
10.0 (perfectly clean).
Shell Four Ball Wear Test
The wear preventative performance of each lubricating oil
composition was determined in accordance with ASTM D4172 under
conditions of 1800 rpm, oil temperature of 80.degree. C. and load
of 30 kg for periods of 30 minutes. After testing, the test balls
were removed, the wear scars were measured, and the wear scar
diameter shown as the result.
Engine Bench Test
Diesel engine test JASO (Japanese Automotive Standards
Organization) detergency test: JASO M336-14): The weighted total
demerit must not exceed 740 and no stuck rings are allowed. Diesel
Engine Test (JASO valve train wear test: JASO M354-15): Evaluation
of wear of the tappets.
The performance of lubricating oil compositions prepared in the
Examples and Comparative Examples were tested using a water-cooled,
4-cylinder, 4-L diesel Hino N04C-VH making 120 kW at 2800 rpm. The
engine is a direct injection turbocharged engine equipped with EGR.
The exact procedure can be found at
https://www.swri.org/sites/default/files/jaso-m336-m354-m362.pdf.
TABLE-US-00002 TABLE 2 Ref. Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex.
7 Kinematic Viscosity (100.degree. C.), mm.sup.2/s 10.6 10.6 10.7
8.1 8.2 8.2 7.3 Viscosity Index 141 158 177 149 170 172 165 CCS
Viscosity, temperature .degree. C. -25 -30 -35 -30 -35 -35 -35 cP
<7000 <6600 <6200 <6600 <6200 <6200 <6200 HTHS
Viscosity (150.degree. C.), cP 3.2 3.2 3.2 2.7 2.7 2.7 2.4 Ca, wt.
% 0.27 0.27 0.27 0.27 0.27 0.27 0.27 Mg, wt. % 0.0010 0.0010 0.0010
0.0010 0.0010 0.0010 0.0010 P, wt. % 0.040 0.040 0.040 0.040 0.040
0.020 0.040 Zn, wt. % 0.048 0.048 0.048 0.048 0.048 0.024 0.048 S,
wt. % 0.12 0.12 0.12 0.12 0.12 0.078 0.12 B, wt. % 0.018 0.018
0.018 0.018 0.018 0.018 0.018 Mo, wt. % 0.016 0.016 0.016 0.016
0.016 0.016 0.016 K, wt. % 0.021 0.021 0.021 0.021 0.021 0 0.021 N,
wt. % 0.069 0.069 0.069 0.069 0.069 0.069 0.069 Sulfated Ash, wt. %
1.07 1.07 1.07 1.07 1.07 1.04 1.07 Komatsu Hot Tube Test Merit
Rating 10.0 10.0 10.0 9.5 10.0 10.0 10.0 Shell 4 Ball Wear Test
Wear Scar Diameter, mm 0.44 0.42 0.40 0.41 0.39 0.41 0.38 Engine
Bench Test-JASO M336: 3014 (JASO M354: 2015) Weighted Total Demerit
(WTD) 740 531 487 466 440 644 -- -- max Stuck Rings (Y/N) N N N N N
-- -- Tappet Wear 11.3 .mu.m max 8.8 10.6 10.1 9.7 9.8 -- --
Carbone residue increase after test, 5.8 3.7 4.7 4.0 4.8 -- -- 3.0%
wt. min. Ex. 8 Ex. 9 Ex. 10 Ex. 11 Ex. 12 Ex. 13 Ex. 14 Kinematic
Viscosity (100.degree. C.), mm.sup.2/s 7.2 7.2 10.6 8.1 8.1 8.1 8.1
Viscosity Index 163 163 158 149 170 170 170 CCS Viscosity
temperature, .degree. C., -35 -35 -30 -30 -35 -35 -35 cP <6200
<6200 <6600 <6600 <6200 <6200 <6200 HTHS
Viscosity (150.degree. C.), cP 2.4 2.4 3.2 3.2 2.7 2.7 2.7 Ca, wt.
% 0.20 0.17 0.27 0.27 0.27 0.20 0.17 Mg, wt. % 0.0010 0.038 0.0010
0.0010 0.0010 0.0010 0.038 P, wt. % 0.040 0.040 0.020 0 0 0 0 Zn,
wt. % 0.048 0.048 0.024 0 0 0 0 S, wt. % 0.11 0.11 0.078 0.038
0.038 0.030 0.034 B, wt. % 0.018 0.018 0.018 0.018 0.018 0.018
0.018 Mo, wt. % 0.016 0.016 0.016 0.016 0.016 0.016 0.016 K, wt. %
0.021 0.021 0.021 0.021 0.021 0.021 0.021 N, wt. % 0.069 0.069
0.069 0.069 0.069 0.069 0.069 Sulfated Ash, wt. % 0.80 0.81 1.04
0.93 0.93 0.08 0.81 Komatsu Hot Tube Test Merit Rating 10.0 10.0
10.0 7.0 7.0 10.0 10.0 Shell 4 Ball Wear Test Wear Scar Diameter,
mm 0.42 0.42 0.41 0.41 0.32 0.37 0.45 Engine Bench Test-JASO M336:
3014 (JASO M354: 2015) Weighted Total Demerit (WTD) 740 -- -- 417
375 -- -- -- max Stuck Rings (Y/N) -- -- N N -- -- -- Tappet Wear
11.3 .mu.m max -- -- 8.5 6.7 -- -- -- Carbone residue increase
after test, -- -- 3.7 4.4 -- -- -- 3.0% wt. min Comp. Comp. Ex.
Comp. Ex. Comp. Ex. Comp. Ex. Comp. Ex. Ex. 1 2 3 4 5 6 Kinematic
Viscosity (100.degree. C.), mm.sup.2/s 7.2 7.2 7.2 10.5 10.5 10.5
Viscosity Index 163 163 163 158 157 157 CCS Viscosity temperature,
.degree. C., -35 -35 -35 -30 -30 -30 cP <6200 <6200 <6200
<6600 <6600 <6600 HTHS Viscosity (150.degree. C.), cP 2.4
2.4 2.4 3.2 3.2 3.2 Ca, wt. % 0.27 0.27 0.27 0.27 0.27 0.27 Mg, wt.
% 0.0010 0.0010 0.0010 0.0010 0.0010 0.0010 P, wt. % 0.040 0.040
0.040 0 0 0 Zn, wt. % 0.048 0.048 0.048 0 0 0 S, wt. % 0.12 0.12
0.12 0.37 0.37 0.37 B, wt. % 0.0020 0.0020 0.018 0.0020 0.0020
0.018 Mo, wt. % 0 0.016 0 0 0.016 0 K, wt. % 0 0 0.021 0 0 0.021 N,
wt. % 0.061 0.061 0.069 0.061 0.061 0.069 Sulfated Ash, wt. % 0.97
1.06 0.98 0.91 0.92 0.92 Komatsu Hot Tube Test Merit Rating 10.0
10.0 10.0 3.0 4.0 4.0 Shell 4 Ball Wear Test Wear Scar Diameter, mm
0.58 0.55 0.51 1.91 0.59 0.53 JASO M336: 3014 (JASO M354: 2015)
Weighted Total Demerit (WTD) 740 -- -- -- -- -- -- max Stuck Rings
(Y/N) -- -- -- -- -- -- Tappet Wear 11.3 .mu.m max -- -- -- -- --
-- Carbone residue increase after test, -- -- -- -- -- -- 3.0% wt.
min
As shown in Table 2, the lubricating oil compositions containing an
organo-molybdenum compound and a dispersed hydrated alkali metal
borate compound provide comparable or superior anti-wear properties
and high temperature detergency and thermal stability to
lubricating oil compositions containing conventional dispersant and
alkaline earth metal detergent at very low viscosity grades, even
if the phosphorus content is at a lower concentration or zero.
* * * * *
References